[0001] According to one aspect, the invention relates to a method of manufacturing fibre-reinforced
parts, such as blades, for wind power plants whereby a number of layers of material
comprising fibre, such as glass fibre mats, are arranged on a curved surface of an
elongated open mould.
Background
[0002] In the context of manufacturing fibre-reinforced parts, such as blades, for wind
power plants, a manufacturing process is typically employed in which a part is moulded
in two halves in each their open mould, wherein a coat e.g. of gelcoat is initially
applied onto the interior surface of the open mould.
[0003] A number of layers of fibre material, or mats, are subsequently arranged in the mould,
typically by hand, following which resin is applied, typically by injection into the
closed mould, to attach the individual layers of fibre material to each other. The
resin can be applied to the layers manually by RTM (resin transfer moulding), VARTM
(vacuum assisted resin transfer moulding) or other suitable methods. Alternatively
the resin can be applied to the laminate layers prior to laying the layers (Prepeg).
In the context of this, gelcoat will harden and form the surface of the product.
[0004] The layers are typically provided to the process as rolls comprising an "endless"
length of material which are arranged on the mould and subsequently cut to fit the
shape of the part to be manufactured.
[0005] Arranging and shaping (by cutting) the layers of fibre material within the interior
of a mould is today a time-consuming and labour intensive process. Depending of the
size of the part to be manufactured, and thereby the size of the mould, walkways may
be arranged alongside and/or above the mould such that the workers are allowed to
walk along the edge or periphery of the mould and/or above the mould in order to arrange
and cut the layers of fibre material as required.
[0006] During the layup of fibre material, combined efforts of several workers are required,
as the fibre material is heavy and not easy manipulable. Some workers assist in the
rollout of material, while other workers positioned along the edge of the mould, make
sure that the layers are laid up correctly.
[0007] In order to secure a desired shape, visual appearance, strength and stability of
the part to be manufactured, it is of outmost importance that the layers are arranged
and cut correctly without dents or wrinkles and the like.
[0008] Depending on the application and structure of the part to be manufactured, multiple
layers of fibre material may be arranged on the mould and the layers are typically
arranged on top of each other or next to each other possibly with overlapping edges.
[0009] The parts typically consist of as many as fifty or more layers of material, and the
parts are typically build up from a main laminate provided in the centre of the mould.
[0010] After a layer, which is provided from a roll, is arranged on the mould, the material
is cut from the roll. Manufacturing of parts having curvature throughout the length
of the part, such as a wing for a wind power plant, may require very long cuts along
the edges of the mould.
[0011] Moulds for manufacturing such parts may be very large, and the moulds are as a consequence
expensive. The time required for the arrangement of material on the mould should be
kept at a minimum such that the form time (the time which a part occupies the mould)
required by a part to be manufactured is kept at a minimum, thus increasing the overall
productivity of the mould.
[0012] GB 2156729 A teaches a method of moulding reinforced materials where a pre-impregnated reinforcement
material, such as a glass fibre mat, is applied to a moulding process. The reinforcement
material may be of "indefinite length", in which case a cutter will be needed for
the process of laying up the laminate, or the mat can be provided to the process in
pre-cut lengths, where the cuts are provided by a cutting station arranged in the
vicinity of the mould. The cutting station is able to cut the material, prior to the
material being arranged onto the mould, in a direction substantially transverse to
the materials direction of conveyance.
[0013] The fibre material is preferably arranged substantially even and flush, which is
why any developed dents, wrinkles or curls and the like should be smoothed out. Further,
as one layer is typically applied on top of a preceding layer, the lower layer incl.
possible additional layers arranged below the lower layer, tend to move or slide within
the mould causing the entire layup of fibre material to move away from an intended
position within the mould. As a consequence, any manipulation or handling of the material
arranged on the mould should be kept at a minimum, which is why a process of manufacture
is desired wherein the step of cutting the mats, while the mats are arranged on the
mould, is eliminated.
[0014] F. C. Campbell, "Manufacturing Processes for Advanced Composites", describes a method
for ply-by-ply arrangement of single plies on a mould. The plies may have been precut
and provided with a ply identification number. The plies are then arranged on carts
and transported to the layup area. The plies are laid up by an operator and a vision
system in form of a laser outlining the position for the next ply to be laid up.
[0015] It is thus an object of the invention to provide a solution to the above drawbacks.
[0016] This is accomplished by the method of manufacturing a fibre-reinforced part as per
the introductory part of this specification, wherein each mat is arranged on the curved
surface of the mould as pre-shaped mats having a form substantially corresponding
to an intended area of application such that any need for further modification of
or cutting in the mat is substantially eliminated.
[0017] The method according to the present invention substantially reduces the required
form time required by the manufacturing of a part, and further, the method is able
to reduce the efforts required by workers in order to lay up the mats.
[0018] The pre-shaped mats are rolled off or drawn from one or more rolls provided on a
gangway or a cart adapted for conveyance along said elongated mould, whereby the odds
of damaging the layers during the layup is greatly reduced and the required manpower
for the layup minimized.
[0019] Further, the one or more rolls are arranged as a "revolver drum" comprising a number
of rolls each comprising different pre-shaped mats, whereby handling of, and access
to the mats accommodated by the rolls are greatly optimized.
[0020] According to one embodiment, the pre-shaped mats constitute pre-cut mats cut from
one or more rolls of material.
[0021] When, as stated in claim 3, the pre-shaped mats are arranged on the mould according
to a pattern of predetermined positions, layup speed as well as the quality of the
final product is increased.
[0022] According to one embodiment, the predetermined positions constitute a pattern established
on the mould by means of light.
[0023] According to one embodiment the pre-shaped mats are provided from a device adapted
to pre-cut an "endless" length of material drawn of a roll. According to one embodiment,
the pre-cut mats are rolled onto one or more rolls and in one or more layers.
[0024] When, as stated in claim 8, the pre-shaped mats are provided with a form of identification,
control and documentation of the layup is facilitated.
Brief description of the figure
[0025]
Figure 1 shows an open mould covered by a layer of fibre mats.
Figure 2 shows pre-shaped fibre mats.
Figure 3 shows an open mould.
Detailed description with reference to the figures
[0026] Figure 1 shows a principal top view of three juxtaposed lengths of fibre material
20 covering an open mould 1 having a curved surface 5 defined by the periphery 6.
The mould 1 and the periphery 6 of the curved surface 5 are illustrated by dotted
lines.
[0027] The mould 1 may typically constitute an elongated mould having a length corresponding
substantially to the length of the part or sub-part to be manufactured.
[0028] According to today's methods of manufacturing fibre reinforced parts, one or more
layers 20, which typically are unrolled from one or more rolls (not shown), are arranged
on the mould 1 such that the curved surface 5 is covered.
[0029] Upon at least one length of material being arranged such that the curved surface
5 is covered, the material is cut along the edge or periphery 6 such that the length
of material, upon being cut, fits an indented position within the mould 1.
[0030] Due to a limited width of the material being provided to the mould 1, one layer of
material is typically made up from several sub-pieces being arranged, either side
by side or with an overlap, on the mould 1.
[0031] Superjacent or overlying layers may be arranged on the mould 1 such that the lines
or areas wherein subjacent or underlying layers meet are covered by the superjacent
or overlying layer, in other words, the position of the matsl being arranged on the
mould 1 may shift in directions substantially perpendicular to a longitudinal axis
of the mould 1.
[0032] As can be seen in the figure, it will typically be necessary to cut along the entire
periphery or edge 6 of the curved surface 5.
[0033] As the moulds for manufacturing components like blades for wind power plants and
the like may be very large, typically in excess of 60 meters, and as many as 50 layers
(stacked or piled) or more are arranged on the mould, the process of cutting the material
is a tremendous task.
[0034] Although not shown in the figures, a main laminate having a relatively great thickness,
possibly as much as 50 mm or more and a width of about 800 mm may be arranged on the
mould 1.
[0035] Further, and not shown in the figures, between the mats, balsa wood may be interposed
in order to obtain a desired distance between the layers of mats. The balsa wood may
also be subjects to the method of manufacture according to this specification.
[0036] Figure 2 shows pre-shaped fibre mats 10 prepared for being arranged onto a mould
1. The pre-shaped mats 10 may be delivered from a sub supplier or manufactured at
an adjacent manufacturing station.
[0037] The pre-shaped fibre mats 10 may be provided to the process as rolled unto one or
more not shown rolls. The rolls may constitute a "revolver drum" (not shown) configured
for accommodating two or more rolls, such that fibre mats with varying properties
and shaped, may be arranged onto the mould 1 without disturbing the process of laying
up one or more layers of fibre material.
[0038] The pre-shaped mats may be provided with markings 11 facilitating layup of the mats
on the mould1.
[0039] The pre-shaped fibre mats 10 may be produced (fabricated or weaved) such that a particular
shape is obtained, or as an equal alternative, cut in shape from a roll of material.
[0040] The means for establishing the cuts may constitute cut-rolls, knives/blades, laser,
any type of blast-cutting, cutting forms and the like, and the process of pre-shaping
the layers may constitute an automated and/or processor controlled process.
[0041] Figure 3 shows an empty and open mould 1. The method of manufacturing a fibre reinforced
part according to the present invention may comprise the step of establishing markings
on the curved surface 5 of the mould 1, or on mats arranged on the mould 1, such as
illustrated by the dotted lines 7. The markings 7 may be established by lightning
or illuminating means (not shown) incl. a laser, provided above the curved surface
5 of the mould 1.
[0042] Upon a layer of material, pre-shaped of not, being arranged on the mould 1, a worker
may align the material according to the markings 7, such that the intended position
of the material on the mould 1 may relatively easily be obtained.
[0043] The lightning means may, for various purposes, be able to alter the markings, e.g.
such that the markings 7 changes upon finalization of a layup.
[0044] Means for recording video or still pictures may be provided such the control and/or
documentation of the process of laying up the material may be provided.
[0045] The lightning means as well as the camera may be controlled by a not shown processor,
such as a computer.
[0046] It must be understood that the invention as disclosed in the present description
and figures can be modified or amended while continuing to be comprised by the protective
scope conferred by the following claims.
1. A method of manufacturing fibre-reinforced blades for wind power plants, whereby a
number of layers (10) of material comprising fibre, such as glass fibre mats, are
arranged on a curved surface (5) of an elongated open mould (1) characterized by that each layer (10) of material is arranged on said curved surface (5) as pre-shaped
mats (10) having a form substantially corresponding to an intended area of application
such that any need for further modification of or cutting in said material is substantially
eliminated, and
wherein said pre-shaped mats (5) are rolled off or drawn from one or more rolls provided
on a gangway or a cart adapted for conveyance along said elongated mould (1), and
wherein said one or more rolls are arranged as a "revolver drum" comprising a number
of rolls each comprising different pre-shaped mats (10).
2. The method according to any of the preceding claims wherein said pre-shaped mats (5)
constitute pre-cut layers cut from one or more rolls of material.
3. The method according to any of the preceding claims wherein said pre-shaped mats (5)
are arranged on said mould according to a pattern of predetermined positions.
4. The method according to any of the preceding claims wherein said pre-shaped mats (5)
are arranged on said mould according to a pattern of predetermined positions indicated
on said mould (1), wherein said pattern are established on said mould (1) by means
of light.
5. The method according to any of the preceding claims wherein said pre-shaped mats (5)
are provided from a device adapted to pre-cut said material.
6. The method according to claim 5 wherein said pre-cut layers (5) are rolled onto one
or more rolls and in one or more layers.
7. The method according to any of the preceding claims wherein said pre-shaped mats (5)
are arranged on said form (1) according to markings provided on said pre-shaped mats
(5).
8. The method according to any of the preceding claims wherein said pre-shaped mats (5)
are provided with a form of identification.
1. Verfahren zum Herstellen von faserverstärkten Flügeln für Windkraftanlagen, wodurch
eine Anzahl von Schichten (10) aus Fasern umfassenden Material, wie etwa Glasfasermatten,
auf einer gekrümmten Oberfläche (5) eines langgestreckten offenen Formwerkzeugs (1)
angeordnet werden, dadurch gekennzeichnet, dass jede Schicht (10) aus Material als vorgeformte Matten (10) mit einer im Wesentlichen
einem vorgesehenen Anwendungsgebiet entsprechenden Form auf der gekrümmten Oberfläche
(5) angeordnet wird, sodass jeder Bedarf an weiterer Veränderung von oder Schneiden
in dem Material im Wesentlichen eliminiert wird, und
wobei die vorgeformten Matten (5) von einer oder mehr Rollen abgerollt oder gezogen
werden, die auf einem für den Transport entlang dem langgestreckten Formwerkzeug (1)
angepassten Laufsteg oder Wagen bereitgestellt werden, und
wobei die eine oder mehr Rollen als "Revolvertrommel" angeordnet sind, die eine Anzahl
von jeweils unterschiedliche vorgeformte Matten (10) umfassenden Rollen umfasst.
2. Verfahren nach einem der vorangehenden Ansprüche, wobei die vorgeformten Matten (5)
von einer oder mehr Rollen aus Material geschnittene, zugeschnittene Schichten bilden.
3. Verfahren nach einem der vorangehenden Ansprüche, wobei die vorgeformten Matten (5)
gemäß einem Muster aus vorherbestimmten Lagen auf dem Formwerkzeug angeordnet werden.
4. Verfahren nach einem der vorangehenden Ansprüche, wobei die vorgeformten Matten (5)
gemäß einem Muster aus auf dem Formwerkzeug (1) angezeigten vorherbestimmten Lagen
auf dem Formwerkzeug angeordnet werden, wobei das Muster mittels Licht auf dem Formwerkzeug
(1) erstellt wird.
5. Verfahren nach einem der vorangehenden Ansprüche, wobei die vorgeformten Matten (5)
ab einer Vorrichtung bereitgestellt werden, die dazu angepasst ist, das Material zuzuschneiden.
6. Verfahren nach Anspruch 5, wobei die zugeschnittenen Schichten (5) auf einer oder
mehr Rollen und in einer oder mehr Schichten aufgerollt sind.
7. Verfahren nach einem der vorangehenden Ansprüche, wobei die vorgeformten Matten (5)
gemäß auf den vorgeformten Matten (5) bereitgestellten Markierungen auf dem Formwerkzeug
(1) angeordnet werden.
8. Verfahren nach einem der vorangehenden Ansprüche, wobei die vorgeformten Matten (5)
mit einer Form der Kennzeichnung versehen sind.
1. Procédé de fabrication de pales renforcées de fibres pour des centrales éoliennes,
ce par quoi un certain nombre de couches (10) de matériau comportant de la fibre,
tels que des mats de fibres de verre, sont agencées sur une surface incurvée (5) d'un
moule ouvert allongé (1) caractérisé en ce que chaque couche (10) de matériau est agencée sur ladite surface incurvée (5) sous forme
de mats préformés (10) ayant une forme correspondant sensiblement à une zone d'application
prévue, de telle sorte que tout besoin de modification supplémentaire ou de découpe
dans ledit matériau est sensiblement éliminé, et
dans lequel lesdits mats préformés (5) sont déroulés ou retirés d'un ou de plusieurs
rouleaux mis en oeuvre sur une passerelle ou un chariot adapté à des fins de transport
le long dudit moule allongé (1), et
dans lequel lesdits un ou plusieurs rouleaux sont agencés sous la forme d'un « cylindre
tournant » comportant un certain nombre de rouleaux comportant chacun différents mats
préformés (10).
2. Procédé selon l'une quelconque des revendications précédentes, dans lequel lesdits
mats préformés (5) constituent des couches prédécoupées découpées en provenance d'un
ou de plusieurs rouleaux de matériau.
3. Procédé selon l'une quelconque des revendications précédentes, dans lequel lesdits
mats préformés (5) sont agencés sur ledit moule selon un motif de positions prédéterminées.
4. Procédé selon l'une quelconque des revendications précédentes, dans lequel lesdits
mats préformés (5) sont agencés sur ledit moule selon un motif de positions prédéterminées
indiquées sur ledit moule (1), dans lequel ledit motif est établi sur ledit moule
(1) au moyen de lumière.
5. Procédé selon l'une quelconque des revendications précédentes, dans lequel lesdits
mats préformés (5) sont mis en oeuvre à partir d'un dispositif adapté pour prédécouper
ledit matériau.
6. Procédé selon la revendication 5, dans lequel lesdites couches prédécoupées (5) sont
enroulées sur un ou plusieurs rouleaux et en une ou plusieurs couches.
7. Procédé selon l'une quelconque des revendications précédentes, dans lequel lesdits
mats préformés (5) sont agencés sur ladite forme (1) en fonction des marques mises
en oeuvre sur lesdits mats préformés (5).
8. Procédé selon l'une quelconque des revendications précédentes, dans lequel lesdits
mats préformés (5) comportent une forme d'identification.